1. Field of the Invention
The present invention generally relates to an apparatus for generating stereoscopic images, and more particularly to an apparatus and a method for generating and outputting stereoscopic images, which enable even an output device adopting an interlaced scheme to use stereoscopic images stored in a scheme of barrier Liquid Crystal Display (LCD) (barrier scheme).
2. Description of the Related Art
In general, typical stereoscopic images are generated through both eyes of a human being, i.e. a difference of the visual angles between the left and right eyes, i.e. binocular disparity. This binocular disparity of the human being is generated because the left eye and the right eye are placed at a short distance therebetween, and because images according to the visual angles of the left and right eyes are different from each other. Thus, in order to imitate a three-dimensional effect created through both eyes of the human being, two cameras are needed to generate these stereoscopic images.
Two methods for generating these stereoscopic images include an interlaced scheme that supports a scheme of shuttered glasses, and a barrier scheme.
FIG. 1 show diagrams (a)-(d) where stereoscopic images are created in the barrier scheme and in the interlaced scheme by apparatuses for generating the stereoscopic images, equipped with the two cameras as stated above. Diagram (a) of FIG. 1 shows pixels sensed with the left camera, and diagram (b) of FIG. 1 shows pixels sensed with the right camera. Diagram (c) and diagram (d) of FIG. 1 show stereoscopic images generated by using diagram (a) and diagram (b). Diagram (c) of FIG. 1 shows stereoscopic images (barrier scheme images) generated in a barrier scheme, and diagram (d) shows stereoscopic images (interlaced scheme images) generated in an interlaced scheme.
For starters, barrier scheme images are created from the left to the right by selecting the pixels sensed with the left and right cameras as in the following. The first single file of the pixels sensed with the left camera is arranged, the second single file of the pixels sensed with the right camera is arranged, the third single file of the pixels sensed with the left camera is arranged, the fourth single file of the pixels sensed with the right camera is arranged, and likewise. Namely, as shown in diagram (c) of FIG. 1, when the first file of the barrier scheme images is extracted from the first file 100 among the pixels sensed with the left camera, the second file is extracted from the second file 102 among the pixels sensed with the right camera. In this way, the pixels sensed with the left and right cameras are extracted by turns from the left to the right, and accordingly, the stereoscopic images are created as shown in diagram (c) FIG. 1, in which the files of the pixels sensed with the left and right cameras are included repeatedly and by turns. This barrier scheme corresponds to a scheme of generating the stereoscopic images, primarily used in mobile terminals, such as mobile phones or the like. When a mobile terminal using the barrier scheme outputs the barrier scheme images, outputting only the pixels detected with the left camera and providing only the pixels detected with the right camera are swiftly repeated. On this account, an optical illusion phenomenon occurs, and users can see the stereoscopic images through this optical illusion phenomenon.
On the other hand the interlaced scheme images are created from the top to the bottom by selecting the pixels sensed with the left and right cameras as follows. The first single rank of the pixels sensed with the left camera is arranged, the second single rank of the pixels sensed with the right camera is arranged, the third single rank of the pixels sensed with the left camera is arranged, the fourth single rank of the pixels sensed with the right camera is arranged, and so on. Namely, as shown in diagram (d) of FIG. 1, when the first rank of the interlaced scheme images is extracted from the first rank 150 among the pixels sensed with the left camera, the second rank is extracted from the second rank 152 among the pixels sensed with the right camera. In this way, the pixels sensed with the left and right cameras are extracted by turns from the top to the bottom, and accordingly, the stereoscopic images are created as shown in diagram (d) of FIG. 1, in which the ranks of the pixels sensed with the left and right cameras are included repeatedly and by turns.
This interlaced scheme is primarily used in television (TV) sets, etc. In the TV sets outputting stereoscopic images by using these interlaced scheme images, shuttered glasses may be also used. While being synchronized with a synchronizing signal provided from the TV set, the shuttered glasses enable a user to watch only the pixels detected with the left camera for any one moment, and enable the user to watch only the pixels detected with the right camera for the next moment. Providing the pixels is rapidly repeated. Therefore, when these shuttered glasses are used, while the TV set supplies the user with the interlaced scheme images, the user watches the ranks of the pixels detected with the left and right cameras by shifts. As a result, an optical illusion phenomenon occurs, and the user can see the stereoscopic images through this optical illusion phenomenon.
Still, as aforementioned, it is usual that the mobile terminal, etc., adopts the barrier scheme. In consequence, if the stereoscopic images are stored in the mobile terminal, these stereoscopic images are stored in the form of the barrier scheme images. Accordingly, when the barrier scheme images are directly provided from the TV set, normal stereoscopic images are not only created, the images themselves are damaged.
FIG. 2 shows diagrams (a)-(c) where stereoscopic images stored in a mobile terminal corresponding to an apparatus for generating images in the barrier scheme are output as images according to an interlaced scheme.
Diagram (a) of FIG. 2 shows barrier scheme images generated by extracting the images sensed with the left and right cameras by turns. Accordingly, when images stored in the barrier scheme are output through the TV set generating the stereoscopic images in the interlaced scheme, the TV set detects a currently input barrier scheme image as an interlaced scheme image, extracts ranks 200 and 202 having odd line numbers or ranks 250 and 252 having even line numbers from the images of diagram (a) of FIG. 2, and outputs the extracted ranks. In this case, on the TV set, as shown in digrams (b) and (c) of FIG. 2, the ranks (i.e. diagram (b)) having the odd line numbers or the ranks (i.e. diagram (c)) having the even line numbers of the reference images (i.e. diagram (a)) are quickly and repeatedly output.
It should be noted that diagram (a) of FIG. 2 illustrates not the interlaced scheme images, but the barrier scheme images. Accordingly, each rank of the images illustrated in diagram (a) of FIG. 2 includes the pixels sensed with the left camera in company with the pixels sensed with the right camera. On this account, the stereoscopic images provided from the TV set include the pixels sensed with the right camera, even though only the screen viewed through the left eye should be output (refer to diagram (b) of FIG. 2), and also includes the pixels sensed with the left camera, even though only the screen viewed through the right eye should be output (refer to diagram (c) of FIG. 2). Consequently, problems appear in that normal stereoscopic images are not only created, the images themselves are damaged.